In the 24 hours since the court handed down its decision Thursday, the Romney campaign took in $4.6 million from more than 47,000 donations online, according to campaign spokesman Andrea Saul, who tweeted the news at 10:20 Friday morning.

At 5:23 Friday morning, the post-decision “take” was already at $4.2 million and more than 42,000 donors, Ms. Saul reported in an earlier tweet.

Within hours of the ruling, the Romney campaign sent out a fundraising e-mail. “Today, the Supreme Court upheld Obamacare. But regardless of what the court said about the constitutionality of the law, Obamacare is bad medicine, it is bad policy, and when I’m president, the bad news of Obamacare will be over,” the e-mail read.

It concluded with the ask: "Donate $10 or more to put a stop to the policies of Barack Obama and the liberal Democrats."

For Mr. Romney, just as important as the cash are the new donors – not only because of their money but because they are potential volunteers. In particular, Romney has struggled to attract small donations. As of the end of May, only 11 percent of his money had come from donors who gave $200 or less, compared with 41 percent for President Obama, according to the Campaign Finance Institute (CFI) in Washington.

Still, the cash is nice. Romney had a good fundraising month in May, but Obama’s was better, according to the CFI.

“Romney’s $23.4 million in receipts doubled his campaign’s $11.7 million of the previous month,” the institute reports. “But Obama’s $39.8 million was 70 percent higher than Romney’s.”